HL7 Explained

1. What is Health Level 7 (HL7)?
2. What does the Name "HL7" mean?
3. How is HL7 organised?
4. Who is Health Level Seven Inc. (USA)?
5. What happens at an HL7.org Working Meeting?
6. Who is HL7 Singapore?
7. Do I need a License to use the HL7 Standards?

What is Health Level 7 (HL7)?

Just as people from different countries with completely different native tongues are only able to communicate with each other if they can speak a common language, computer applications can only share information if they communicate with a common protocol. For people or computers to be able to share clinical data with one another, they must both:

1. have functions to be able to physically communicate, e.g. speak & hear, send and receive documents and data files, share data and information. This is called "functional interoperability".
2. speak a common language (in terms of nouns, verbs, grammatical structure, etc.) and share the same vocabulary that allows them to understand complex medical conditions and processes. This is called "semantic interoperability".

A group of healthcare computer systems users started developing the HL7 protocol in 1987 to create a common "language" that allows healthcare applications to share clinical data with each another. Over time the HL7 interoperability protocol became a nationally, internationally and globally accepted and accredited standard.

The term "Health Level 7" ("HL7") is used both for the organisations involved in developing and supporting the healthcare standards as well as for the Version 2.x and Version 3 Standards themselves and other standards developed by the HL7 local organisations in ~30 countries. HL7 creates international standards for inter-system and inter-organisation messaging, for decision support, clinical text document mark-up, user interface integration as well as a health data model and a message development methodology.

A frequent misconception is that Health Level Seven develops software. In reality, HL7 develops specifications, the most widely known being a messaging standard that enables disparate healthcare applications to exchange clinical and administrative data.

Members of Health Level Seven are known collectively as the Working Group, which is organized into Technical Committees (TCs) and Special Interest Groups (SIGs). The technical committees are directly responsible for the content of the Standards. Special interest groups serve as a test bed for exploring new areas that may need coverage in HL7 published standards. A list of the technical committees and special interest groups as well as their missions, scopes and current leadership is available on the HL7.org web site.

Recent years have seen a move toward an increasingly global HL7. From 9 Affiliates in 1999, HL7 has grown to ~30 international affiliates in 2006. Currently, the worldwide membership is over 4,400. The global scope also involves increased collaboration with other regional and international standards organizations, such as CEN in Europe and the International Standards Organisation (ISO). HL7 has achieved ISO status for its standards and is moving toward harmonization with the CEN standards.

The HL7 organisation has formal relationships with other major Standards Development Organisations (SDOs), including:

• ASTM (American Society for Testing Materials)
• CEN TC/251 (Europe)
• DICOM (Digital Imaging and Communication in Medicine)
• IEEE (Institute for Electrical and Electronic Engineers)
• OASIS
• OMG (Object Management Group)

The full list of organisational relationships and agreements can be viewed here.

All standards and documents produced by HL7 are protected under copyright law (see "Do I need a licence to use HL7" below). Copies of the HL7 standards can be purchased from HL7 Singapore.

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What does the Name "HL7" mean?

HL7 Standards and Tools"Level Seven" refers to the top level of the seven-layer International Standards Organization's (ISO) communications model for Open Systems Interconnection (OSI) - the application layer. The application level addresses definition of the data to be exchanged, the timing of the interchange, and the communication of certain errors to the application. The seventh level supports such functions as security checks, participant identification, availability checks, exchange mechanism negotiations and, most importantly, data exchange structuring. (More info on the 7-layer ISO communications model at: http://en.wikipedia.org/wiki/OSI_model)

HL7 focuses on the interface requirements of the entire health care organization, while most other efforts focus on the requirements of a particular department. HL7 undertakes ongoing development of protocols on the fastest possible track that is both responsive and responsible to its members. The group addresses the unique requirements of already installed hospital and departmental systems, some of which use mature technologies.

While HL7 focuses on addressing immediate needs, the group continues to dedicate its efforts to ensuring concurrence with other United States and International standards development activities. Argentina, Australia, Bulgaria, Canada, China, Czech Republic, Finland, Germany, India, Japan, Korea, Lithuania, The Netherlands, New Zealand, Southern Africa, Singapore, Switzerland, Taiwan, Turkey and the United Kingdom are part of HL7 initiatives. Moreover, HL7 is an American National Standards Institute (ANSI) approved Standards Developing Organization (SDO). HL7 strives to identify and support the diverse requirements of each of its membership constituencies: Users, Vendors, and Consultants. Cognizant of their needs, requirements, priorities and interests, HL7 supports all groups as they make important contributions to the quality of the organization. The committee structure, balanced balloting procedures and open membership policies ensure that all requirements are addressed uniformly and equitably with quality and consistency.

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How is HL7 organised?

The organization is managed by a Board of Directors, which is comprised of eight elected positions and three appointed positions. The organization is comprised of Technical Committees and Special Interest Groups that are responsible for defining the HL7 standard protocol. Each Technical Committee and Special Interest group is chaired by two or more co-chairs. The TCs and SIGs are grouped into Steering Divisions, which comprise the Technical Steering Committee, which votes on issues related to the standard. The Board of Directors has strategic oversight over the TSC. HL7 members are encouraged to participate in all of these committees.

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Who is Health Level Seven Inc. (USA)?

Health Level Seven Inc. (USA) is one of several ANSI-accredited Standards Developing Organizations (SDOs) operating in the American healthcare arena. Most SDOs produce standards (sometimes called specifications or protocols) for a particular healthcare domain such as pharmacy, medical devices, imaging or insurance (claims processing) transactions. Health Level Seven domain is clinical and administrative data.

Headquartered in Ann Arbor, USA, Health Level Seven is a not-for-profit volunteer organization - like most of the other SDOs. Its members - providers, vendors, payers, consultants, government groups and others who have an interest in the development and advancement of clinical and administrative standards for healthcare - develop the standards. Like all ANSI-accredited SDOs, Health Level Seven adheres to a strict and well-defined set of operating procedures that ensures consensus, openness and balance of interest.

For more information on HL7 (USA) see:

• the "About HL7" page on the HL7.org web site
• The frequently asked questions on HL7 (USA) page on the HL7.org web site
• The latest HL7.org Newsletters
• The HL7.org Press Releases and Press Release Archive

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What happens at an HL7.org Working Meeting?

HL7 is organized around Technical Committees (TCs) and Special Interest Groups (SIGs). These committees are responsible for defining the HL7 Standards. TCs are responsible for at least one chapter in one of the HL7 Standards, while SIGs work closely with TCs to ensure that information within their particular domain is considered and represented in the Standards. Two or more co-chairs, who develop meeting agendas and ensure that the work of the group proceeds as scheduled, chair each TC and SIG. The TCs and SIGs are represented in four Steering Divisions which in turn constitutes the Technical Steering Committee (TSC).
You will be able to quickly identify Board and TSC Members at the meeting by the ribbons on their name badges. TC and SIG meetings are held throughout the week, are open to all meeting attendees and are informal in nature, so don't be afraid to simply show up and get involved! The HL7 Staffers will be onsite during the week; so don't hesitate to stop by should you have a question.

HL7 offers a very useful First Timers Attendees Orientation which is held both on Sunday evening and on Monday morning. Also, look for the "First Time Attendee" designated lunch tables on Monday and Tuesday to meet with other first-time attendees and seasoned members who have volunteered to help you learn the ropes. Each day, the HL7 Working Group Meeting begins at 8:30 a.m. with an informative general session for announcements and dissemination of general information such as changes in meeting rooms and/or times. Technical Committees (TC), Special Interest Groups (SIG), and tutorials begin following the general session.

HL7 Working Group Meetings always provide a vast array of educational opportunities. Over 20 tutorials are scheduled for the Working Group Meeting on topics such as Implementing HL7, V2.x, V3, XML, CDA and HL7's Vocabulary initiatives. Please refer to the Working Group Meeting Brochure for course descriptions.
 

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Who is HL7 Singapore?

HL7 (Singapore) is an open, not-for-profit organization to support the development, promotion and implementation of HL7 standards in ways that meet the needs of healthcare organizations, healthcare professionals and healthcare IT practitioners in Singapore. HL7 Singapore was registered with the Singapore Registrar of Societies (ROS) on the 3 June 2008 and officially launched on 27 June 2008. The HL7 Singapore constitution can be viewed here. For more information about HL7 Singapore see the about HL7 Singapore page

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Do I need a License to use the HL7 Standards?

In general:

• HL7 is a volunteer, not-for-profit organisation; distribution fees and membership fees support its operation.
• The HL7 Standards underlie a strict copyright; unauthorised copying is not permitted
• Use of the Standards within organisations that are HL7 Members is fine
• The copying of substantial parts (>10%) of the Standards for commercial or educational purposes requires a license agreement

The HL7.org Copyright Policy (2000) states:

To ensure that the HL7 Standards are not inappropriately modified or abridged, they underlie a strict copyright. As a result, if a substantial part of any HL7 Standards document is to be used in any commercial or non-commercial products or services (paper or electronic manuals, interface engines, educational materials, etc.), an appropriate license must be obtained from HL7 or its Affiliates. The Affiliates manage the HL7 intellectual property ("IP") rights in their respective territories. Additionally, as HL7 levies a small fee on copies of the standards it provides (similar to the "distributions" of Linux, Apache, Open Office or other free software) the unauthorised distribution of the standards is not legal.